Plastic bags killing Queensland’s turtles

A group of University of Queensland researchers are urging Queenslanders to avoid littering the state’s marine environment during the upcoming Easter holiday weekend.

Led by Dr Kathy Townsend, Manager of Research and Education at UQ’s Moreton Bay Research Station, the group found that marine rubbish was the leading cause of sea turtle deaths in 2007.

“In 2007, we attended to 30 marine turtle strandings,” Dr Townsend said. “Of these, 23 percent were caused by the ingestion of marine rubbish. “This is almost double the number for 2006 in which marine rubbish accounted for 12 percent of the strandings.”

Dr Townsend said, regardless of its size, marine rubbish posed a serious threat to sea turtles. “A green turtle hatchling, six centimetres in length, washed up on North Stradbroke and died due to gut perforation through the ingestion of plastic marine rubbish,” she said.

“Its gut contained plastic bags, soft and hard plastic, and fishing line. The piece that killed the baby turtle was only about half the size of a fingernail. “Another turtle, a sub-adult, died with a gut full of plastic bags, the largest of which was over 30 centimetres long.”

Sea turtles are particularly susceptible to the effects of marine rubbish due to the internal structure of their throats and die a slow and painful death.

“Sea turtles have downward facing spines in their throats which literally prevent them from regurgitating,” Dr Townsend said. “The plastic gets trapped in the gut, preventing food from going down and the spines prevent it from coming back up.

“The trapped food decomposes, leaking gases into the body cavity and causing the animal to float. “The turtle then slowly starves to death or succumbs to other secondary life threatening conditions such as boat strike.”

Boat strikes have traditionally been the greatest cause of marine turtle strandings but, according to the group’s findings, accounted for only 17 percent in 2007.

“Plastic bags do kill and the recent federal initiative of a plastic bag levee is a step in the right direction towards helping address this problem,” Dr Townsend said.